aspire 5520 blinking power light

[uberthug]

This laptop is giving me ****, The first time I fixed this laptop (acer aspire 5520). I just disassembled and reassembled it and ran start up repair. The owner (I'm disabled and fix computers for people that can't afford it while I study for the a+ cert) brought it back with the same symptoms. when turned on the power on light and fan comes on then goes out and then the power on light blinks with the hard drive light blinking now and then. I tried a hard boot and I disassembled and reassembled completely, tested memory and memory slots took cpu to local repair shop and it tested clean the owner said the start up repair came up a few times right before the failure so I started with the hard drive no errors in the mbr and the hard drive works fine on different computer. any help would be great I'm trying to fix as soon as possible as owner is bed bound and her computer is her whole life

 

[Lexluethar]

Is the power adapter on the motherboard loose? IF so it may need to be soldered back into place.

 

[uberthug]

I checked the power supply I've checked everything and at this point the only thing left is the motherboard, It's a really nice laptop I'm debating on spending the 175 for a new board.